Lomborg-errors:
"Cool
it!"
|
|
Temperatures on Greenland and Antarctica |
|
Home Cool it |
"Cool it!", chapter 3: Global warming: Our many worries
Pages
64 - 66.
To those who want a recent overview of
the subject, I may recommend:
A. Cazenave & W. Llovel (2010): Contemporary sea level rise. Annual
review of marine science 2: 145-173.
I. Allison et al. (2009): Review: Ice sheet mass balance and sea level.
Antarctic science 21 (5): 413-426.
I will also recommend reading the
chapters on Greenland and Antarctica in Howard Friel (2010): The Lomborg Deception.
GENERAL COMMENTS: |
TEMPERATURES ON GREENLAND: |
Lomborg writes (p. 64) that 1941 is still the varmest year recorded
on
Greenland, and that the 1930s and 1940s still are the two warmest
decades there.
In response to this, John Cappelen,
meteorologist at the Danish Meteorological Institutet, DMI, says
that the truth is more complicated, because Greenland is large,
and the trends are not the same at the seven stations where
temperatures have been followed. He also says that at the east coast,
2003 is the
warmest year on record, whereas at Nuuk (the "capital",
situated in south west Greenland), 1941 and 2003 were equally
warm. Altogether, the record year is 2003 rather than 1941.
The temperatures for three weather stations at
the west coast of Greenland are to be found on the internet here. The
average for Nuuk was +0.83° in 1941, and +0.51° in 2003, i.e.
slightly lower. So Lomborg is right as to the west coast of Greenland,
but not as to Greenland in total.
It may be added that the extent of ice melting on
Greenland is steadily increasing, see here and here.
The
most
recent
information
is
that
the
extent
of melting reached a new
record in 2007, and that air temperatures above the ice are have
increased by about 4° C since 1991, see this
link.
Remember that melting consumes heat
energy and tends to lower temperatures. If you put a clump of ice
in a jar and supply a heat source to melt the ice slowly, the
temperature in the jar
will remain constant - at exactly 0° C - as long as there is
still ice left in the jar. It is only when all ice has melted that
water
temperatures start to rise. So if there is a lack of local
temperature rise at the weather stations at the coast, this cannot be
used as an argument that there
is no increase in ice melting.
The temperature trends for Greenland are not typical for
the whole arctic region, as is evident in Przybylak (2000), cited by
Lomborg.
ANTARCTIC TEMPERATURES : |
Lomborg writes (p. 65) that the only part of Antarctica that is
warming is the west Antarctic peninsula which makes out only
4 % of the total land area; the remaining 96 % has become
colder. But this is not true.
Temperatures for those Antarctic weather stations
with the longest time series are found at this link.
It is seen here that since the mid 20th century, annual temperatures
have increased significantly at the west Antarctic Peninsula and in one
coastal station on mainland Antarctica. At all other weather stations,
including the South Pole, there is no significant trend. In a few
stations there is a significant negative trend for autumn temperatures,
but not for annual temperaturs.
Others have said the same as Lomborg, viz. that 96 %
of the Antarctic continent is cooling. This information goes back to a
paper by Peter
Doran et al. in 2002 in Nature (link). They found (by a different type of analysis)
that 58 % of Antarctica had
cooled from 1966 to 2000, especially regarding autumn temperatures,
whereas the rest, i.e. 42 %, had
warmed, including the west Antarctic peninsula that makes out 15
% of the area.
The cooling of parts of the continent is partially
due to the ozone hole. According to Doran, as the ozone hole
heals - thanks to worldwide bans on ozone-destroying chemicals -
all of Antarctica is likely to warm with the rest of the planet.
The summary of the paper in Nature pointed out
how the cooling trend posed challenges to models of Antarctic
climate. American newspaper and television reports focused on
this part of the paper, and claimed that these scientific
findings ran counter to the theory of global warming. Since then,
climate skeptics have cited this information over and over again.
Although the scientists have written rebuttals and explained that
the media have misunderstood the information, the
misinsterpretation has quickly become legend among skeptics, and
is cited ever more often. A refutation written by Peter Doran in
The New York Times may be read here.
THE LARSEN-B ICE SHELF |
Critics pose that the breakup of
ice shelves is not due to
man-made global warming, because these ice shelves have disappeared
before. This criticism is unjustified. The Larsen-B ice shelf has
existed without interruption since the ice age (Domack
et
al.
2005, Curry
&
Pudsey
2007), and its breakup is ascribed to man-made global
warming (Marshall
et al 2006). Also the IPCC report (4AR wg1 paragraph 4.6.3.4) says:
" . . the ice
shelf changes have resulted from environmental warming . . "" Before
the 2002 breakup of the Larsen B Ice Shelf, local air temperatures had
increased by more than 1.5°C over the previous 50 years ..
increasing . . formation of large melt ponds on the ice shelf. These
likely contributed to breakup . . ".
PENGUINS IN DANGER? |
Lomborg criticises the way that
the decline of a population of emperor penguins is presented in Al
Gore´s book "An Inconvenient Truth". However, as
explained on the Lomborg-errors page
on
Al
Gore, for page 178 in Gore´s book, there is very little
flaw in Al Gore´s text. On the basis of data from G.L. Kooyman,
Lomborg infers that there may have been increases in certain emperor
penguin populations on the Ross ice shelf; however, a new paper
co-authored by Kooyman states that the colonies referred to have had no
significant changes up to now, except that one out of six colonies (one
not referred to by Lomborg) has had a small increase. Also, new
information from 2009 says that the studied colony of emperor penguins
is expected to decline very much during this century because fo changes
in sea ice (Jenouvrier & Caswell (2009): Proceedings national
academy of
sciences USA 106(6): 1844-1847).
As to Adélie penguins, which require winter pack ice, Lomborg
only talks about increase, referring to a site in east Antarctica. But,
according to WWF, the species is severely declining in some places and
increasing in others (link).
One
of
the
references
that
Lomborg has read
(Vaughan 2001) talks about a colony that has persisted by at least 600
years, but which is now declining. Lomborg omits to mention that.
Flaws on
particular
pages in
Lomborgs text:
FLAW
Page 63 top (various end notes)
Flaw: The references to
the IPCC report that are written as fig. 10.6.1, fig. 10.6.3 and fig.
10.6.4 should actually have been paragraph 10.6.1, paragraph 10.6.3 and
paragraph 10.6.4.
FLAW
Page 63 top: "Antarctica will not noticeably start melting . . .
actually be accumulating ice . . . "
Flaw: This is not true,
and it relies on Lomborg´s selective reading of his sources. See
the review articles at the top of this page for better and more recent
information.
FLAW
Page 63 bottom: "Some analyses have shown more rapid loss in recent
years . . . "
Flaw: This is a biased
wording. All analyses have shown much more rapid loss in recent years.
Lomborg´s statement that by early 2007 two of the major glaciers
in Greenland were again seen reverting to much lower rates is not
justified. He cannot, when writing his book in 2007, base anything on
what has happened just within that same year. A person with alleged
expertise in statistics should never extrapolate a trend from just one
year and suggest that this might tell anything about what we could
expect in the future. Actually, the rapid loss has continued after
2007, and the data strongly suggest an ever accelerating mass loss, as
described in the papers listed at the top of this page (Cazenave;
Allison). Lomborg´s note has an estimate of a contribution from
Greenland to sea level rise of about 0.28 mm per year. Since then, this
estimate has nearly tripled to 0.75 mm per year after 2006 (van
den Broeke et al. (2009): Science 326: 984-986.)
FLAW
Page 63 bottom: "Even with the most extreme estimates of Greenland
melting . . . "
Flaw: This does not
fully agree with the paper by Parizek
&
Alley that Lomborg has read. Here, on page 1023, their worst
case scenario has a contribution from Greenland to sea level rise of
5.82 m by the year 2500.
FLAW
Page 63 bottom - page 64 top: "In a recent overview of all the major
models . . . "
Flaw: Lomborg refers to
a paper by Oerlemans et al. (2005). It reports runs with five climate
models, few are none of which are AOGCMs (i.e. they do not include both
atmosphere and ocean). They are all performed on IPCC´s B2
scenario, in which the emission of CO2 grows
considerably more slowly than what is actually the case at present.
Furthermore "the dynamic response of glaciers is not considered", i.e.
the types of acceleration of glaciers that is seen recently are
disregarded. Therefore, the model outputs have less melting than what
may actually be expected. Lomborg´s term "all the major models"
suggests to the reader that all likely outcomes are covered by the
study, which is not the case, as it deals only with the B2 scenario.
FLAW
Page 64 top: "In another overview, all models clearly show . .
. "
Flaw: Lomborg relies
much on the reference Gregory & Huybrechts (2006). However, this
paper suffers from a shortcoming which was also seen in Oerlemans et
al. (2005): it does
not include dynamical responses of glaciers. It says in the first
paragraph: "Such accelerated flow leads to increased ice discharge into
the ocean, but the relevant dynamical processes are not properly
understood nor included . . . This therefore represents an important
uncertainty for predictions of sea level, but one which is beyond the
scope of this paper to address." So the Gregory & Huybrechts paper
does not deal with all contributions to sea level rise. Actually, the
present state of knowledge (2010), as stated in the papers cited on top
of this page, is that Greenland as well as Antarctica give a net
contribution to sea level rise.
FLAW
Page 64: "The IPCC estimates that the very worst additional increase .
.
. "
Flaw: Here Lomborg refers to a paper
by
Parizek
&
Alley that estimates the possible extra melt of Greenland ice that
may occur if dynamic response of glaciers turns out to be important.
The estimate is that this may contribute with up to 20 cm of extra sea
level rise in this century. There are three scenarios, with temperature
increases over Greenland by 2130 of 3.2°, 5.8° and 8.4° C,
respectively. The scenario with the highest temperature rise
corresponds roughly to the most C-intensive IPCC scenario (A1FI). The
actual rate of increase in CO2 concentrations by now is
actually a little higher than this worst IPCC scenario (links here
and here),
that
is,
if present trends continue, the situation will correspond to
more than an 8.4° C temperature increase over Greenland, which will
yield the 20 cm extra sea level rise referred to above. However, the
paper states (p. 1020) that the climate computer model used falls
toward the low end of sensitivities. So in reality the rise could
possibly be even larger.
ERROR
Page 65: ". . while the other 96 percent of Antarctica has cooled "
Error: This
is not true. Lomborg gives three references. The first is Chapman &
Walsh (2005), which has now been published in Journal of Climate 20
(16): 4096-4117. According to this paper, there has been a generally
warming trend for the Antarctic continent for the period 1958-2002. In
most parts of the continent, this trend is not significant. Only small
parts of the continent have seen a cooling trend. The second is a
website of a climate-sceptic (Humlum). The third is an unpublished
talk; the authors of that talk have later (2007) published a
paper in which new Antarctic temperature analysis suggests recent
warming. As explained above, the claim that 96 percent has cooled is a
mistake derived from the media´s false interpretation of a paper
by Doran et al. (2002). It is peculiarly
troubling that Lomborg´s claim is against the contents of
two of his sources.
FLAW
Page 65: "The South Pole has seen its temperature decline . . . "
Flaw: As stated above,
there is no significant temperature decline at the South Pole, maybe
not even a decline at all (Chapman & Walsh 2005, cited above).
ERROR
Page 65: ". . believing that Larsen B has been intact . . . "
Error: Larsen
B
has
indeed
been
intact
continuously
since
the last ice age. It is
true that parts of "the Larsen area" had its ice sheets broken up some
thousand years ago, but these parts were further to the north,
including the Larsen A ice shelf (Pudsey et al. 2006, cited by
Lomborg). Larsen B has not been broken up (E. Domack et al. (2005):
Nature 436 (3908): 681-685), and its breakup in 2002 when summer
temperatures were unusually warm is therefore an indication of more
warmth than ever before since the last ice age. Lomborg has seen a
paper by Marshall et al. (2006), which refers to the Domack paper and
says: "Marine sediments from below where the farthest
south of these sections, the Larsen B shelf, was formerly located,
indicate that its collapse is unique within the Holocene period." So
Lomborg knew this, but stated
otherwise in this text.
<FLAW
Page 65 bottom - 66 top: "While it probably led to ice shelves floating
more quickly . . . "
Flaw: This is an
understatement. After the collapse of the Larsen B ice shelf, the
movement of inland glaciers behind the ice shelf accelerated by a
factor of 2 to 8 (Rignot et al (2004): Geophys res. lett. 31(18):
L18401; Scambos et al. (2004): Geophys
res.
lett.
31(18):
L18401;
Rignot
(2006):
Phil-
trans. Royal Soc. A
364: 1637-1655.)
ERROR
Page 66 top: "The precipitation on the Antarctic Peninsula is
increasing . . . and this likely outweighs the melting "
Error:
Lomborg´s use of the references is very selective here. For
instance he cites Zwally et al. (2005) in which there is a single
station on the peninsula showing net accumulation of ice, whereas the
same study shows that West Antarctica in total has a large net loss of
ice. Morris and Mulvaney (2004) indicate a net increase of ice
on the peninsula with future warming (which gives more precipitation),
and state that for each degree of warming, the effect on global sea
level will be ÷ 0.006 mm. However, warming will also increase
the discharge of glacier ice by ablation, that is melting, sublimation
and calving, and for each degree of temperature rise, this will
contribute + 0.07 mm to global sea level, provided that meltwater can
find its way into the sea. Thus, the net effect of melting may be much
greater than the net effect of snow accumulation. Although Lomborg
touches on this aspectin his note, he avoids the crucial circumstance
that precipitation will probably not outweigh melting. This is deliberate distortion of the
information he has read.
FLAW:
Page 66 top: " . . . the Antarctic Peninsula is probably participating
in an overall lowering of sea
levels."
Flaw: There are
indications to the opposite. Firstly, Morris & Mulvaney (2004)
indicate that the removal of ice by various processes, especially
melting, may possibly outweigh snow accumulation in the future.
This was explained above. In addition, however, there is an effect of
accelerating glaciers. Because glaciers are thinning at their ends,
they
are now moving faster towards the sea than before. This is described in
Pritchard & Vaughan (2007): Journal of geophysical research 112
F03S29. They estimate that the net contribution of the Antarctic
Peninsula to global sea level from this glacier acceleration and other
processes is + 0.16 mm per year. Also van de Berg et al. (2006):
Journal of geophysical research 111 D1104 find that the mass balance of
the peninsula is probably negative. This is directly opposite what
Lomborg
states.
ERROR
Page 66: "This too is the story of the continent."
Error:
No, it is not. For instance, Lomborg has cited Zwally et al. (2005) as
a source for accumulation of ice and snow on the peninsula. But in the
same source there is a total estimate of mass gain or loss on
Antarctica. There is an estimated total loss of 47 gigaton ice on the
whole of west Antarctica, which is not fully conuterbalanced by an
estimated gain of 16 giga ton on east Antarctica. This gives a net loss
of 31 giga tons per year, which contributes to sea level increase, not
decrease. When Lomborg has read this, but nevertheless says the
opposite, he is deliberately
misleading. Many other references likewise indicate a net loss
of ice on the Antarctic continent.
ERROR
Page 66 - 67 top: " . . . a decrease
in sea levels in all models. "
Error: This
is contrary to the contents of the 2007 IPCC report WG 1, according to
which Antarctica gives a net positive contribution to sea level rise.
Lomborg does not indicate which models he is talking about.
But
in
the British version of the book, he refers to the paper by
Gregory & Hubrechts,
which
has
the
shortcomings described above for page 64 top.
ERROR
Page 67 top: " . . . all models predict ever more net accumulation over
this century. "
Error: This
is contrary to the trends right now, when there is probably an
increasing net contribution to sea level rise (see for instance Allison
et al. 2009, cited at the start of this page). See
also
the
previous comment here.